Due to the geographic coverage nature of wireless service, there are hundreds of thousands of cell towers in the United States. For example, in 2014, it was estimated that there were more than 310,000 cell towers in the United States. Cell towers can have heights up to 1,500 feet or more. There are various requirements for cell site workers (also referred to as tower climbers or transmission tower workers) to climb cell towers to perform maintenance, audit, and repair work for cellular phone and other wireless communications companies. This is both a dangerous and costly endeavor. For example, between 2003 and 2011, 50 tower climbers died working on cell sites (see, e.g., www.pbs.org/wgbh/pages/frontline/social-issues/cell-tower-deaths/in-race-for-better-cell-service-men-who-climb-towers-pay-with-their-lives/). Also, OSHA estimates that working on cell sites is 10 times more dangerous than construction work, generally (see, e.g., www.propublica.org/article/cell-tower-work-fatalities-methodology. Furthermore, the tower climbs also can lead to service disruptions caused by accidents. Thus, there is a strong desire, from both a cost and safety perspective, to reduce the number of tower climbs.
Concurrently, the use of unmanned aerial vehicles (UAV), referred to as drones, is evolving. There are limitations associated with UAVs, including emerging FAA rules and guidelines associated with their commercial use. It would be advantageous to leverage the use of UAVs to reduce tower climbs of cell towers. US 20140298181 to Rezvan describes methods and systems for performing a cell site audit remotely. However, Rezvan does not contemplate performing any activity locally at the cell site, nor various aspects of UAV use. US 20120250010 to Hannay describes aerial inspections of transmission lines using drones. However, Hannay does not contemplate performing any activity locally at the cell site, nor various aspects of constraining the UAV use. Specifically, Hannay contemplates a flight path in three dimensions along a transmission line.